Culture
Easily grown in acidic, medium moisture, well-drained soils in full sun to part shade. Best fruit production occurs in full sun, but plants generally appreciate some part afternoon shade in hot summer climates. Best sited in locations protected from cold winter winds. Avoid poorly drained soils. Mulch will help retain soil moisture and deter weed growth. Prune in winter if needed. Plants are dioecious (separate male and female plants). In order to set fruit, female plants will need a nearby male pollinator. Plants are not reliably winter hardy throughout USDA Zone 5.
Noteworthy Characteristics
Ilex × attenuata is a naturally occuring hybrid originally found growing in the wild in Florida in 1924. It is a cross between I. cassine (dahoon) and I. opaca (American holly), both of which parents share native territory in the far southeastern U.S. (particularly from coastal North Carolina to Florida). This hybrid is a conical evergreen shrub or small tree that grows over time to 12-25’ tall or more, unless pruned shorter. It is commonly called topel holly, although some of the named cultivars thereunder have different common names (e.g. I. x attenuata 'Fosteri' plants are commonly called foster hollies). Hybrid cultivars grow in a variety of different forms and habits, but generally exhibit (a) spiny, elliptic to obovate-lanceolate evergreen leaves (to 3” long) with attenuated bases, (b) insignificant greenish-white spring flowers and (c) showy, pea-sized, red fruits that persists over winter. Fruits are ornamentally attractive. Birds are attracted to the fruit.
Genus name comes from the Latin name Quercus ilex for holm oak in reference to the foliage similarities (holm oak and many of the shrubs in the genus Ilex have evergreen leaves).
The hybrid name attenuata means narrowing to a point, possibly in reference to the growth habit of this hybrid.
‘Savannah’ is a narrow, columnar to open pyramidal form that was discovered by W. H. Robertson, Commissioner of Parks in Savannah, Georgia, and has been available in commerce since 1953. It typically grows as a small tree to 20’ (infrequently to 30’) tall and to 15’ wide. It is noted for producing extremely showy, florescent, red fruit that is quite ornamentally attractive in fall and winter. In the deep South, ‘Savannah’ is a very popular landscape plant. Plants have sparsely-spined, light green, elliptic to ovate, evergreen leaves (to 4” long). Showy, pea-sized, red fruits appear in fall, often profusely, and persist over winter. Greenish-white spring flowers are inconspicuous. Light gray bark. Birds are attracted to the fruit.
Problems
Potential insect problems include holly leaf miner, spittlebugs, spider mites, whitefly and scale. Potential disease problems include leaf spot, leaf rot, tar spot and powdery mildew. Plants are also susceptible to leaf drop, leaf scorch and chlorosis (yellowing of leaves in high pH soils).
Uses
Hedges or screens. Specimen or small groups. Foundation plantings. Foliage and fruit provide good color for the winter landscape. Train as a small tree.
In the deep South, plants are used as street trees.